1. Field of the Invention
The present invention relates to a measuring device for an object or an article.
2. Background Information
Measuring devices have been conceived in which a plurality of hoppers are arranged circumferentially, and operations of supplying, measuring and discharging the objects are performed while circulating these hoppers.
According to the invention of the Japanese Utility Model Publication No. H4-069731 (pp. 4-5, FIG. 1), three operations, i.e., supplying, measuring and discharging the objects are performed intermittently in a circular manner for obtaining objects having a predetermined weight quickly. According to this prior art, however, since the measuring is performed after the objects are supplied, it is difficult to supply objects accurately. Therefore, it is difficult to ensure the accuracy in the weight of objects obtained.
According to the invention of the Japanese Laid-Open Patent Publication No. 2000-185719 (p. 4, FIG. 2), although the intermittent operation is performed likewise, two measuring portions and two supply portions are arranged so that an operation of supplying a large amount of objects is performed together with a supplying operation whereby an error in the weight is corrected. Thereby, objects having a predetermined weight can be obtained quickly with improved weight accuracy. According to this arrangement, however, the supplying and measuring operations are performed at different positions on the circular path, respectively. Therefore, it is difficult to achieve sufficiently high accuracy in supply amount. Furthermore, the weighing device tends to have large sizes.
According to the invention of the Japanese Laid-Open Patent Publication No. H9-002401 (pp. 2-3, FIG. 1), supplying and measuring of a large mount of objects are performed simultaneously, and thereafter, supplying (for the purpose of correcting error in weight) and measuring of a smaller amount of objects are performed simultaneously. Further, these supplying and measuring operations are continuously performed. Thereby, higher accuracy is ensured in weight of objects obtained, and the fast operation is achieved. However, this device requires many measuring devices and many supplying devices for achieving the fast operation. Further, the device must control many devices, and thus requires complicated control. Still furthermore, since the measuring device moves, accurate measuring is difficult as compared with the measuring in a stationary position.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for improved measuring devices that overcome the aforementioned problems of the conventional art. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.